The uniforms are a sort of drab olive-khaki. See here for a reference:
http://www.replicaters.com/naziuniforms.html Look at the NSDAP uniform, which is the most recognizable and has the skirt.
The really distinctive thing about the uniform is the red armband; without that, the uniform is similar to other uniforms of the era.
Two other comments: Your guy is wearing short boots, but the Nazi boots came all the way up to the knee; he also seems to be wearing a gas mask and helmet. The gas mask I don't know much about, but the helmet would be black, I think, like this:
http://militaria.polarhaven.net/GermanMilitaria/Nazi%20Police%20Helmet%202-Decal.JPG.
Right now, with the monotone grey, he looks sort of like an Imperial Stormtrooper in the shadow.
(Also, hi, first post.)